为已知的未知事件做准备相当困难，除非你重视他们。
It's extremely hard to prepare for the known unknowns until you take them seriously.
超过15,000人的平民在此前的未知事件中丧生。
More than 15, 000 civilians died in previously unknown incidents.
超过15,000人的平民在此前的未知事件中丧生。
More than 15,000 civilians died in previously unknown incidents.
水晶球实际上是玻璃球，据说能从中看到未知事件的画面。
A crystal ball is actually a glass ball, in which the fortuneteller is supposed to be able to see a picture of some future event.
推测类问题：读者必须推测未知事件，因为他们身在文本之外。
Speculative questions: the reader has to speculate about things which are unknowable, because they are outside the text.
推测类问题：读者必须推测未知事件，因为他们身在文本之外。
Speculative questions: the reader has to speculate about things which are unknowable, because they are outside the text.
当火星轨道器遭遇未知事件时，其程序会使其进入安全模式。
The orbiter is programmed to go into safe mode when it encounters an unknown event.
虽然研究人员还无法解释一些未知事件，如新发现的致死性疾病和大规模流行病的发生，但他们的预测有助于全球健康规划的制定。
Although the researchers can not explain some unknown events, such as the newly discovered fatal diseases and large-scale epidemic, but they help to forecast the development of global health planning.
GerardJouany，一位航空记者表示，后备系统显示飞行员曾经用无线电进行联络，并称这次悲剧是诸多未知事件一齐导致的结果。
Gerard Jouany, an aviation journalist, said that back-up systems would allow the pilots to radio, and said the tragedy must have been a combination of events that are unknown.
但是，伊朗可能会引发中东地区的核军备竞赛，还需要与中国、印度这样正在崛起的新兴超级大国进行稀缺资源的激烈竞争，还有现在尚无人可知的未知事件。
Violent competition over scarce resources may erupt with or between emerging superpowers, such as China and India. And so on into the unknown unknowns.
但是，伊朗可能会引发中东地区的核军备竞赛，还需要与中国、印度这样正在崛起的新兴超级大国进行稀缺资源的激烈竞争，还有现在尚无人可知的未知事件。
Violent competition over scarce resources may erupt with or between emerging superpowers, such as China and India. And so on into the unknown unknowns.
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